472 Recently piiblis/ied Ornithological Works. 



Taylor on Dominancy. 



[Dominancy in Nature and its Correlation with Evolution, Plij'logeny, 

 and C4eograpliical Distribution. Presidential Address delivered at the 

 51st Annual Meeting of the Yorkshire Naturalists' Union, at the Royal 

 Institution, Hull, on March 20, 1913. By John W. Taylor.] 



The thesis which Mr. Taylor sets himself to prove is that 

 the region of the earth where competition and the struggle 

 for existence is most severe, and where consequently only the 

 most highly organized and well equipped forms of animal 

 life have survived, is the north-central portion of Europe. 



Mr. Taylor is a malacologist of considerable repute, and 

 most of his argument is based on a study of the land 

 Mollusca of the world, but on page 22 he attempts to show 

 that Dominaucy in bird life also has its culminating point 

 in western Europe, illustrating his remarks by instancing the 

 Jays, the Coal-Tits, and Grey Shrikes, in all of which cases 

 the most specialized forms inhabit western Euro])e, while the 

 more primitive forms are found in Asia and Noith Africa. 



Trotter on the Fimnal Regions of North America. 



[The Faunal Divisions of Eastern North America in Relation to 

 Vegetation. By Spencer Trotter, M.D. Journ. Acad. Nat. Sci. Philad. 

 XV. 1912, pp. 207-218.] 



The current classification of North American faunal areas 

 is that of Dr. C. Hart Merriam, who divides the North 

 American Continent into two dominant zones extending 

 across its entire breadth — a Boreal and Sonorau, the first of 

 which has environmental conditions and a fauna closely 

 resembling that of the northern zone of Eurasia. These and 

 other minor and intermediate divisions are almost entirely 

 based on difterences of temperature alone. 



Dr. Trotter believes that a truer classification of faunal 

 areas can be reached by taking other factors into considera- 

 tion as well as temperature, especially atmospheric precipi- 

 tation and soils, and he would follow Schimper, who recognizes 

 three types or formations of vegetable life — Woodland, 

 Grassland, and Desert. 



